Ndjili International Airport lies in the tropics at 4.39° S, 15.44° E, on Africa/Kinshasa time (UTC+1). Tropical airports contend with heat and humidity, both of which thin the air and lengthen takeoff runs, and with convective storms that build fast in the afternoon.
Ndjili International Airport has 1 runway. The longest, 06/24, measures 13,123 ft by 197 ft, which puts the field in the full-length intercontinental category: a fully loaded Boeing 777 or Airbus A350 can depart for the far side of the world. The surface is concrete. It is lit for night operations.
Runway 06/24 is aligned roughly north-east/south-west, which is the clearest hint you get about the prevailing wind here: runways are built to face the wind that blows most often, because aircraft take off and land into it. Every runway here shares that north-east/south-west alignment, so a strong crosswind means a crosswind landing rather than a switch to another strip.